[digidocs]

A fun weight saving fact:

There are about 425 AN365-1032s in your RV-10. If you replace them all with MS21042-L3s you'll save about 1.7 lbs.

If you return the AN365s to Van's and buy the MS21042s from Spruce, it will cost about $109 or $64/lb.

David

 

[David Paule]

Those particular nuts are lubricated and need different torques than the nuts in the kit. It's not merely the locking torque that't affected, it's the basic torque.

Anyone have any idea what the torque shuld be?

Dave

 

[digidocs]

Dave,

It looks like the spread between a -3 and and dry film lube -L3
is small and much less than the natural variation among different nuts of the
same type.

David

Citation: http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA024893

 

[beav]

A fun weight saving fact:

There are about 425 AN365-1032s in your RV-10. If you replace them all with MS21042-L3s you'll save about 1.7 lbs.

If you return the AN365s to Van's and buy the MS21042s from Spruce, it will cost about $109 or $64/lb.

Another option to consider is AN364 nuts. Everywhere that I've needed a nut where clamping force isn't critical and bolts are loaded only in shear (adel clamps, seat belt attach bolts, etc.), I've used these. I imagine there are quite a number of other places on the airframe that could use these, but I would want to run those past Van's or a sufficiently qualified engineer.

 

[N15JB]

A fun weight saving fact:

There are about 425 AN365-1032s in your RV-10. If you replace them all with MS21042-L3s you'll save about 1.7 lbs.

If you return the AN365s to Van's and buy the MS21042s from Spruce, it will cost about $109 or $64/lb.

David

That is cheap compared to high end bicycles. Figure on about $1000 per pound to lower the weight on a good bike. We have a 21 lb. tandem that cost more than 4 years of college(back in the 60s)

Jim Berry
RV-10

 

[chrish]

I think most reading this could reduce the weight of the total take off weight by at least 1.7 lbs by going for a walk every day

 

[JonJay]

I think most reading this could reduce the weight of the total take off weight by at least 1.7 lbs by going for a walk every day

And add "do your business" as part of you preflight

I would gladly pay $64 a pound if you find another 60 of these changes to shave #100 from my 6. ( I'm not giving up my 180hp or CS etc....)

The reality is, the basic bare airframe is pretty well designed and all the little things I see posted, when added together, still make very little overall difference.

 

[digidocs]

All the little savings add up! Here are a few others that seem to be good wins:

- LiFePO4 battery (~10 lbs, $30/lb) over a PC680
- 2 blade composite CS prop (10-15 lbs, ~$100/lb)
- Cheap tires with less rubber (can be 2+ lbs per wheel, $0/lb)
- ECI tapered fin cylinders (~3lb, $???)
- Lighter and less instruments/avionics (TT22 transponder weighs 0.8 lbs, MGL V6 com or similar weighs 0.5 lbs, no vacuum pump, simple EFIS instead of steam gauges)
- Replace engine hoses with SS hardlines (one -8 builder reported 7 lbs)
- Less interior/insulation

Saving weight is so fun!

David

 

[HIIFLY]

CHEEP THIN TIRES !

Ever had a FLAT at a field away from home base ? That day I wish I had solid rubber tires ! Ha . and I would have paid plenty $$$$$ to have them .

 

[Low Pass]

All the little savings add up! Here are a few others that seem to be good wins:

- LiFePO4 battery (~10 lbs, $30/lb) over a PC680
- 2 blade composite CS prop (10-15 lbs, ~$100/lb)
- Cheap tires with less rubber (can be 2+ lbs per wheel, $0/lb)
- ECI tapered fin cylinders (~3lb, $???)
- Lighter and less instruments/avionics (TT22 transponder weighs 0.8 lbs, MGL V6 com or similar weighs 0.5 lbs, no vacuum pump, simple EFIS instead of steam gauges)
- Replace engine hoses with SS hardlines (one -8 builder reported 7 lbs)
- Less interior/insulation

Saving weight is so fun!

David

I'm guilty of several of the items above. Just reduced hose weight by 15 oz (one long run) by rerouting. Saved 5 lbs (yes, 5!) going from heavy, Hooker harnesses to Crow. New starter time after 1500 hrs (good excuse anyway), saved 1.8 lbs with the new XLT Sky Tec. Oh yea, two P-mags as well... Next step, Grove gear legs.

And yes, I need to get out and walk more to reduce front seat occupant loads. But these other things are icing on the cake!

Thanks for the work on the MS21042 nuts. Excellent idea!

 

[smokyray]

Weight a minute...

All the little savings add up! Here are a few others that seem to be good wins:

- LiFePO4 battery (~10 lbs, $30/lb) over a PC680
- 2 blade composite CS prop (10-15 lbs, ~$100/lb)
- Cheap tires with less rubber (can be 2+ lbs per wheel, $0/lb)
- ECI tapered fin cylinders (~3lb, $???)
- Lighter and less instruments/avionics (TT22 transponder weighs 0.8 lbs, MGL V6 com or similar weighs 0.5 lbs, no vacuum pump, simple EFIS instead of steam gauges)
- Replace engine hoses with SS hardlines (one -8 builder reported 7 lbs)
- Less interior/insulation
Saving weight is so fun!
David

David,
Great thread! It seems this thought process has gone by the wayside in the modern "cookie cutter" RV world. For us Jurassic RV builders, low empty weight and cost savings was everything. The first line in Van's RV8R Newsletter completions back in the day was empty weight (the second was cost to complete). Now it seems the reverse is the case, more weight, more cost. Having flown several RV's in the past 25 years, the light weight airplanes simply fly better and faster regardless of HP. Funny how that works...

Since my current RV-X and my previous RV-4 tipped the scales under 950 Lbs, I will add a few more audacious ideas I have seen and used...
1. NO cockpit upholstery or insulation. Colored NASA foam for seats.
2. Minimum or NO electrical system. (B&C SD8, ATV battery or Photoelectric cell)
3. Minimum panel. How about an iPad only,...and Good Lord forbid, no autopilot!
4. Manual flaps, period.
5. NO exterior paint. Or, only ONE coat of color/primer.
6. 0-320, (or light 0-360) Composite FP prop, Magnesium flywheel.
7. P-mags or electronic Ignition, (1/2 weight of mags, I weighed them)
8. Handheld Radio, PLB, ADS-B

The list goes on, but the logic of saving weight on bolts and nuts is awesome. However comma, adding a full panel, multicolor paint, autopilot and Angle valve IO-360/Hartzell is like ordering a Big Mac and fries with a diet Coke, just doesn't compute...

V/R
Smokey

 

[David Z]

RV-8 Manual Flaps

If I could put manual flaps in my RV-8, I'd be on that like a fat kid on cake. I haven't found a plane with manual flaps that I don't like and I've flown with several different makes/models. There's really no electric flaps that I do like. Haven't flown an RV yet, so maybe there is one that I like

 

[JonJay]

All the little savings add up! Here are a few others that seem to be good wins:

- LiFePO4 battery (~10 lbs, $30/lb) over a PC680
- 2 blade composite CS prop (10-15 lbs, ~$100/lb)
- Cheap tires with less rubber (can be 2+ lbs per wheel, $0/lb)
- ECI tapered fin cylinders (~3lb, $???)
- Lighter and less instruments/avionics (TT22 transponder weighs 0.8 lbs, MGL V6 com or similar weighs 0.5 lbs, no vacuum pump, simple EFIS instead of steam gauges)
- Replace engine hoses with SS hardlines (one -8 builder reported 7 lbs)
- Less interior/insulation

Saving weight is so fun!

David

All good points David - but none affect the airframe. When it comes to the basic airframe, ideas like changing hardware that started the thread, have very little overall benefit.
Still, very good reminder for all where weight can be saved in areas that do not affect structure...
and, keeping Smokey's record intact, 100% agree.

 

[David Paule]

List of Weights of Things

I've been keeping a record of the weights of some things that I've gotten for my RV-3B. I'm listing them in this format:

The system they go into,
The part description,
Weight in grams,
Weight in pounds,
Any notes if applicable.

Lights
AeroLEDs Microsun
101.8 g
.22 lb

Fuel system,
Van's brass fuel selector valve and handle, stock, no bezel or fittings,
208 g,
.46 lb

Fuel system,
Andair FS 20X7T fuel valve, handle and bezel and fittings,
244.1 g,
.46 lb,
(the bezel is 15 or 16 grams alone)

Autopilot,
GRT roll servo,
997 g,
2.20 lb.

Autopilot,
GRT pitch servo,
1023 g,
2.26 lb.

Autopilot,
Dynon servo with limit bracket,
931 g,
2.05 lb.

Autopilot,
GRT servo harness,
256 g,
.56 lb.

Autopilot,
Dynon servo harness kit,
310 g,
.68 lb.

Electrical wire,
4 ga. welding wire, 100 inches,
399 g,
.88 lb.

Oil cooler,
Van's stock OIL COOLER II,
887 g,
1.96 lb.

Oil cooler,
Earl's 21000ERL,
447 g,
.99 lb.

Ignition,
P-Mag 114, without gear, without plug,
1497 g,
3.30 lb.

Ignition,
P-Mag 114, with gear, without plug,
1610 g,
3.55 lb.

P-Mag plug adapters, set of 8, with rings,
188 g,
.41 lb,
In plastic bag.

Ignition,
NGK BR8ES spark plug, one, with gasket ring,
55 g,
.12 lb.

Prop governor,
PCU5000-X,
954 g,
2.10 lb.

Oil drain valve,
Fumoto Engineering T202N, NPT 1/2-14,
160 g,
.35 lb.

Oil filter adapter,
Lycoming 77852 clone, no gasket or filter,
398 g,
.88 lb.

Hardware,
AN509-8R8 screws, 1/2" long, 50 of them,
66.7 g,
.15 lb,
My RV-3B has about 200 for both wings - replace with MS24694S3 below.

Hardware,
MS24694S3 screws, 3/8" long, 50 of them,
48.9 g,
.11 lb.

Instruments
8-Day Clock, Wittenauer
182 grams
.40 lb.

Instruments
ASI, 2 1.4”
195 g
.43 lb

Instruments
Trig TB-90 comm head
90 g
.20 lb

Instruments
SV backup battery
400 g
.88 lb

Instruments
7” Dynon Skyview EFIS
1,250 g
2.76 lb

Instruments
RV-3B panel blank, edge strip
647 g
1.43 lb

Instruments
Slip indicator
12 g
.03 g

Instruments
Honeywell TL switches for panel
196 g
.43 lb

Instruments
11” iPad Pro, 2018
472 g
1.04 lb.

Prop governor,
PCU5000-X,
954 g,
2.10 lb.

Oil drain valve,
Fumoto Engineering T202N, NPT 1/2-14,
160 g,
.35 lb.

Oil filter adapter,
Lycoming 77852 clone, no gasket or filter,
398 g,
.88 lb.

Sensor kit
Dynon kit for 4-cyl Lyc, carb engines
1,362 g with packaging
3.00 lbs